1104 
appears at the bottom and determining graphically the point of 
intersection with the three-phase line, g might be found. 
Fig. 7. 
Fig. 8 gives the P-7' projection for a mixture z,, which has a 
concentration smaller than «,. The point Ar has entered the meta- 
stable region, so that the upper limit of the Z-G region here also 
Fig. 8. 
is indicated by the disappearance of the meniscus at the bottom. 
Here the point #r can only be realized, when the solid phase does 
not appear. The stable part of the L-G loop must offer everywhere 
retrograde phenomena. If the composition on the critical line varies 
only slightly when the temperature rises, the point kr in fig. 8 also 
will move rapidly from a to lower temperatures, when 2, differs 
slightly from z,. The point g is never to be realized with a mixture 
©, ey, though here as well a will deviate slightly from q when 
the difference between «x, and z, is small. 
